The woman was found by her son-in-law, who checked Grullon’s Bronx apartment after not seeing her for several days. She had been stabbed multiple times and was covered by a blanket, police said.

After Batchelor’s arrest for fare evasion, police discovered a previous court order for a DNA sample and forced the suspect to give one.

That ordered had stemmed from a drug-selling charge in 2013 to which Batchelor pleaded guilty, police said. But Batchelor did not comply with the demand to submit a sample for New York’s criminal database, authorities said.